Multiple component mixers

ABSTRACT

A device for the mixing and dispensing a multiple component composition wherein variation is made to the ratio of constituent materials fed to the mixer without having a substantial effect on the total quantity of constituent composition fed to the mixer.

United States Patent Robbins Feb. 15,1972

MULTIPLE COMPONENT MIXERS Inventor: John E. Robbins, Leicester, England USM Corporation, Flemington, NJ.

Oct. 6, 1969 Assignee:

Filed:

Appl. No.:

Foreign Application Priority Data Oct. 25, 1968 Great Britain ..50,648/68 US. Cl ..222/ 135, 222/255, 222/278 ..B67d 5/02 FieldofSearch ..222/135, 134, 70,137,253,

References Cited UNITED STATES PATENTS Diehl & McCargo ..222/255 X 2/1956 l/l95l l/1963 7/1963 3/1964 11/1968 Conklin ..222/255 Thompson ..222/135 X Lewis-Smith ..222/135 Loeser ..222/135 X Little ..222/ 134 X Radcliffe ..222/70 Primary ExaminerRobert B. Reeves Assistant ExaminerThomas E Kocovsky Att0rneyW. Bigelow Hall, Richard A. Wise and Aubrey C.

Brine ABSTRACT A device for the mixing and dispensing a multiple component composition wherein variation is made to the ratio of constituent materials fed to the mixer without having a substantial effect on the total quantity of constituent composition fed to the mixer.

7 Claims, 2 Drawing Figures sum 1 [1F 2 lrwen for John E Rabbi m9 551 hzeAftor'rze-y PATENTEDFEB 1 5 m2 NQ B K MULTIPLE COMPONENT MIXERS BACKGROUND OF THE INVENTION The present invention relates to improvements in apparatus for use in dispensing a composition provided by the mixing together of two or more constituent materials.

There are many and varied uses for apparatus for dispensing a multiple component composition, such apparatus frequently comprising a mixing chamber and means for supplying constituent compositions of the mixture to the mixing chamber wherein the constituent compositions are mixed and dispensed therefrom. Such apparatus often is used to dispense a multiple component composition provided by two individually stable compositions which when mixed together, react chemically.

For example, in U.S. Pat. No. 3,409,174, issued Nov. 5, 1968 and assigned to the assignee of the present invention, there is described apparatus for use in dispensing a polyurethane composition and in the use of which the constituent compositions, comprising polyhydroxyl composition and isocyanate composition, are fed in sequence in a desired ratio, to a mixing chamber. The apparatus also comprises means whereby the ratio at which the compositions are fed to the mixing chamber may be varied, and means whereby the total quantity of constituent composition fed, in a desired ratio, to the mixing chamber, may be varied.

One of the difficulties encountered in apparatus of the kind set out in the last preceding paragraph is that generally convenient and accurate control of the ratio may be attained only with expensive and complicated design of the apparatus.

SUMMARY OF THE INVENTION It is therefore one of the various objects of this invention to provide apparatus for use in dispensing a multiple component composition which provides convenient control of the ratio in which the constituent compositions are mixed.

There will be described hereinafter, to illustrate the invention by way of example, an illustrative dispensing apparatus. The illustrative apparatus is similar in certain aspects to the apparatus described in the specification of the above-mentioned U.S. Patent to which specification reference may be made for clarification of certain aspects not described herein in detail.

The illustrative apparatus is adapted for use in dispensing a multiple component composition, and will be described in its use in the mixing of polyhydroxyl and isocyanate compositions in the dispensing of a polyurethane composition.

The illustrative apparatus generally comprises a mixing chamber of variable volume provided by a cylinder and piston, to which is secured a piston rod, fitting snugly therein, and first and second storage devices in which first and second constituent compositions comprising, respectively, reactive hydroxyl groups and reactive isocyanate groups, are maintained under a pressure in excess of atmospheric pressure. The illustrative apparatus also comprises feeding means comprising first and second feeding devices adapted to feed first and second constituent composition, respectively, from their respective storage devices to the mixing chamber, and correlating means adapted to control the operation of the feeding devices.

The first feeding device comprises a cylinder having a piston, to which is secured a piston rod, slidably mounted therein, and the second feeding device comprises a piston, to which is secured a piston rod, slidably mounted therein.

The feeding means also comprises correlating means associated with the first and second feeding devices and movable by operating mechanism of the feeding means to cause the feeding devices to feed constituent composition from the storage devices towards the mixing chamber. The correlating means comprises a correlating member provided by an elongated bar mounted on a pivot. In one embodiment, free end portions of the piston rods of the two feeding devices are bifurcated, a roller of each feeding device extending between the bifurcated portions thereof through one of two slots of the correlating member. The operating mechanism comprises a cylinder having a piston, to which is secured a piston rod, slidably mounted therein, the piston rod providing an operating member of the feeding means, a free end portion of which piston rod is bifurcated, a roller extending between the bifurcated portions extending through a slot in the correlating member which slot is located between the two other said slots of the correlating member.

The distance between the pivotal mounting of the correlating member and the piston rod of the operating means is variable. The pivot on which the correlating member is mounted is carried on a bracket slidably mounted on a support arm; by moving the bracket along the support arm, the pivot may be moved towards and away from the three piston rods, the rollers of the bifurcated end portions thereof moving within the three slots.

The three piston rods of the feeding means are parallel, and the piston rods of the feeding devices extend from the correlating member' in opposite directions.

A first supply conduit extends from the first storage device through a first one-way valve thereof to an upper portion of the cylinder of the first feeding device; extending from the supply conduit, downstream of the one-way valve through a second one-way valve to the mixing chamber is a first delivery conduit.

A second supply conduit extends from the second storage device through a first one-way valve thereof to a lower portion of the cylinder of the second feeding device; extending from the second supply conduit downstream of the one-way valve through a second one-way valve to the mixing chamber is a second delivery conduit.

The device is so constructed that the ratio of the transverse distances between the piston rod of each feeding device and the piston rod of the operating means is equal to the inverse ratio of the cross-sectional areas of the cylinders of the feeding devices. Thus, variation of the ratio'by movement of the pivot does not substantially vary the said total quantity.

The above and other of the various objects and several features of this invention will become more clear from the following description, to be read with reference to the drawings, of the illustrative apparatus. It is to be understood that this apparatus has been selected to illustrate the invention by way of example only, and not by way of limitation thereof.

BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding of the invention, reference should be had to the accompanying drawings, wherein:

FIG. 1 is a schematic view of the illustrative apparatus showing feeding means thereof in a first condition; and

FIG. 2 is a schematic view of the illustrative apparatus of FIG. 1 showing said feeding meansin a second condition thereof.

The illustrative apparatus is adapted for use in dispensing a multiple component, polyurethane composition, and comprises a mixing chamber 10 of variable volume provided by a cylinder 12 and a piston 14, to which is secured a piston rod 16, fitting snugly therein. Connected to an end portion of the piston rod 16 remote from the piston 14 is a piston 18 slidably mounted in a cylinder 20. On admission of fluid under pressure to an inlet port 21 of the cylinder 20, the piston 14 may be moved within the cylinder 12 to decrease the volume of the mixing chamber 10, air flowing from the cylinder 20 through an exhaust port 22 thereof.

Extending into the cylinder 12 at lower portions thereof are first and second inlet ports 24, 26 respectively. Extending from the cylinder 12 at a lower portion thereof is an outlet port 28 controlled by an outlet valve (not shown), and mounted in the cylinder is a stirrer 30.

The illustrative apparatus also comprises first and second storage devices comprising first and second tanks 32 and 34 respectively in which first and second constituent compositions, comprising, respectively, reactive hydroxyl groups and reactive isocyanate groups, are maintained under a pressure in excess of atmospheric pressure, and feeding means comprising first and second feeding devices 36, 38 respectively adapted to feed first and second constituent composition, respectively, from their respective storage devices to the mixing chamber 10.

The first feeding device 36 comprises a cylinder 40 having a piston 42, to which is secured a piston rod 44, slidably mounted therein. Extending into an upper portion of the cylinder 40 is an inlet port 46 and extending from a lower portion of the cylinder is an exhaust port 48. A free, lower end portion of the piston rod 44 is bifurcated, a roller 50 extending between the bifurcated portions thereof.

The second feeding devices 38 comprises a cylinder 52 having a piston 54, to which is secured a piston rod 56, slidably mounted therein. Extending into a lower portion of the cylinder 52 is an inlet port 58 and extending from an upper portion of the cylinder is an exhaust port 60. A free, upper end portion of the piston rod 56 is bifurcated, a roller 62 extending between the bifurcated portions thereof.

The feeding means also comprises correlating means associated with the feeding devices 36 and 38 and operating mechanism 64 adapted to move the'feeding means between first, second and rest conditions and thereby move the correlating means to cause the feeding devices 36 and 38 to feed constituent composition from the storage devices to the mixing chamber. The correlating mechanism comprises a correlating member 66, provided by an elongated bar, mounted on a pivot 68. The pivot 68 is carried on a bracket 70 slidably mounted on a support arm 72.

The member 66 is provided with three slots 74, 76 and 78, extending lengthwise of the member and spaced at intervals from the pivot 68, respectively.

The operating mechanism 64 comprises-a cylinder 80 having a piston 82, to which is secured a piston rod 84, slidably mounted therein, ports 86, 88 extending into upper and lower portions of the cylinder, respectively. A lower end portion of the rod 84 is bifurcated, a roller 90 extending between the bifurcated portions thereof.

The illustrative apparatus also comprises control mechanism comprising a microswitch 92 secured to an upper end portion of the rod 84, a first contact 94 mounted at a fixed position on a support 96 and a second contact 98 mounted at an adjustably variable position on the support 96.

The piston rods 44, 56 and 84 are parallel, the rollers 50, 62 and 90 thereof extending through the slots 78, 74 and 76 of the correlating member 66, respectively. The piston rods 44 and 84 extend from the correlating member 66 in the same direction, the piston rod 56 extending therefrom in the opposite direction.

A first supply conduit 100 extends from the first storage tank 32 through a first one-way valve 102 to the inlet port 46 of the cylinder 40; extending from the supply conduit 100, downstream of the valve 102 through a second one-way valve I04 to the inlet port 24 of the cylinder 12 is a supply conduit 106.

A second supply conduit 108 extends from the second storage tank 34 through a first one-way valve 110 to the inlet port 58 of the cylinder 52. Extending from the supply conduit I08, downstream of the valve 110 through a second one-way valve 112 to the inlet port 26 of the cylinder 12 is a supply conduit 114.

The illustrative apparatus is shown with the feeding means thereof in a rest condition in broken lines in FIG. 1. in the rest condition, the mixing chamber contains a small amount of first constituent composition together with residual polyurethane composition from an immediately preceding use of the apparatus.

On operation of a starter switch (not shown) of the control mechanism, fluid under pressure is admitted to the port 88 of the cylinder 80, the port 86 thereof and the port 21 of the cylinder 20 being opened by the control mechanism to at mosphere.

The operating mechanism moves the correlating member 66 clockwise (FIG. 1) about its pivot 68, forcing first constituent composition from the cylinder 40 through the port 46 along the conduits and 106 through the one-way valve 104 and into the mixing chamber through the port 24. A proportionate quantity of second constituent composition is fed simultaneously into the cylinder 52 from the second tank, said quantity depending upon the position of the pivot 68 as located along the support arm 72.

On engagement of the microswitch 92 with the contact 98, (with the apparatus in the condition shown in FIG. 1) the control mechanism reverses the direction .of movement of the piston 82, fluid under pressure being admitted to the port 86 and the port 88 being opened to atmosphere.

The correlating member is now moved anticlockwise about the pivot 68, forcing the piston 54 downwardly to feed a proportionate quantity of second constituent composition from the cylinder 52 along the conduits 108 and 114 through the one-way valve 112 and into the mixing chamber 10 through the port 26. Simultaneously, a second quantity of first constituent composition is fed into the cylinder 40 from the first tank 32.

On reaching the position in which it is shown in FIG. 2, in which the feeding means is in its second condition, the operating mechanism is maintained stationary while the constituent compositions are mixed within the mixing chamber 10 and discharged by the piston 14 therefrom through the port 28.

The operating mechanism is then caused by the control mechanism to move the correlating member 66 to its rest condition (shown in dotted lines of FIG. 2), a'small amount of first constituent composition being fed to the mixing chamber 10 to dissolve residual polyurethane composition and simultaneously a proportionate amount of second constituent composition being fed into the cylinder 52. On reaching the shown rest condition, the microswitch 92 engages the contact 94 and the apparatus comes to rest.

The total quantity of first and second constituent composition fed to the mixing chamber 10 may be varied by movement of the contact 98 along the support 96. Such movement of the contact 98 has no effect on the ratio in which the two constituent compositions are fed to the mixing chamber 10.

In accordance with one aspect of the invention, the ratio of the transverse distances, from the connection of the piston rod 44 to the member 66 and the connection of the piston rod 84 to the member 66 (d,) to the connection of the piston rod 56 to the member 66 and from the connection of the piston rod 84 to the member 66 (d is equal to the inverse ratio of the cross-sectional areas of the cylinders 40 (A,) and 52 (A as designated in FIG. 1. Thus, the total quantity of constituent compositions fed to the mixing chamber in any one operation of the illustrative apparatus is independent of the distance of the pivot 68 from the piston rods. Thus, variation may be made to the ratio in which the two constituent compositions are fed to the mixing chamber (by movement of the bracket 70 on the support arm 72) without having any substantial effect to the total quantity of constituent composition fed to the mixing chamber.

In this manner, convenient and accurate control of the mixed composition produced by use of the apparatus may be obtained.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. Apparatus for use in dispensing a composition provided by the mixing together of at least two constituent c'omposi-. tions and comprising first storage means for containing a first of said contituent compositions, second storage means for containing a second of said constituent compositions, means for mixing constituent compositions, first and second cylindrical chambers of different diameters and having pistons slidable therein in one direction to feed one composition from the first storage means to the first chamber while the other composition is fed from the second chamber to the mixing device, said pistons being slidable in the opposite direction to reverse the actions of the chambers; correlating means comprising a pivoted member connected to the pistons and means connected to said member between the connections for said pistons for operating said member to operate the pistons alternately in said directions, the ratio of the distances between the respective connections for the pistons of the first and second chambers and the connection for the operating means being equal to the inverse ratio of the diameters of the respective first and second chambers, the relation of said connections to the pivot of said member being so arranged as to cause said pistons to feed a predetermined ratio of said first and second compositions.

2. Apparatus according to claim 1 including means to adjust the distance between said pivot and the connection of the operating meansfor varying the ratio of said first and second compositions fed by the pistons and maintaining constant the total quantity of the compositions fed.

3. Apparatus according to claim 2 including means to vary the extent of movement of said correlating member for varying the total quantity of the compositions fed and maintaining constant the ratio of the first and second quantities fed.

4. Apparatus for use in dispensing a composition provided by the mixing together of at least two constituent compositions and comprising first feeding means operable to feed a first of said constituent compositions and comprising a cylindrical chamber having a piston slidably disposed therein,

second feeding means operable to feed a second of said constituent compositions and comprising a cylindrical chamber having a piston slidably disposed therein, said cylindrical chambers being of different diameters, correlating means controlling the operation of the first and second feeding means according to an operating ratio equal to the inverse ratio of the diameters of the first and second cylinders, said correlating means being adjustable for varying the effectiveness of said operating ratio to vary the ratio of the quantities of the compositions fed and maintaining constant the total quantity of the compositions fed.

5. Apparatus as set forth in claim 4 wherein said correlating means comprises a pivoted member connected to the two pistons and further including operating means for moving said correlating member about its pivot and connected to said co rrelating member between said piston connections to said correlating member, the ratio of the distances between the connections of the first and second pistons and the operating means being equal to the inverse ratio of the diameters of the first and second chambers.

6. Apparatus according to claim 5 including means to adjust the distance between said pivot and the connection of the operating means for varying the ratio of the respective quantities fed by the first and second feeding means and maintaining constant the total quantity of the compositions fed.

7. Apparatus according to claim 5 including means to vary the extent of movement of the correlating member for varying the total quantity of the compositions fed and maintaining constant the ratio of the respective quantities fed by the first and second feeding means. 

1. Apparatus for use in dispensing a composition provided by the mixing together of at least two constituent compositions and comprising first storage means for containing a first of said contituent compositions, second storage means for containing a second of said constituent compositions, means for mixing constituent compositions, first and second cylindrical chambers of different diameters and having pistons slidable therein in one direction to feed one composition from the first storage means to the first chamber while the other composition is fed from the second chamber to the mixing device, said pistons being slidable in the opposite direction to reverse the actions of the chambers; correlating means comprising a pivoted member connected to the pistons and means connected to said member between the connections for said pistons for operating said member to operate the pistons alternately in said directions, the ratio of the distances between the respective connections for the pistons of the first and second chambers and the connection for the operating means being equal to the inverse ratio of the diameters of the respective first and second chambers, the relation of said connections to the pivot of said member being so arranged as to cause said pistons to feed a predetermined ratio of said first and second compositions.
 2. Apparatus according to claim 1 including means to adjust the distance between said pivot and the connection of the operating means for varying the ratio of said first and second compositions fed by the pistons and maintaining constant the total quantity of the compositions fed.
 3. Apparatus according to claim 2 including means to vary the extent of movement of said correlating member for varying the total quantity of the compositions fed and maintaining constant the ratio of the first and second quantities fed.
 4. Apparatus for use in dispensing a composition provided by the mixing together of at least two constituent compositions and comprising first feeding means operable to feed a first of said constituent compositions and comprising a cylindrical chamber having a piston slidably disposed therein, second feeding means operable to feed a second of said constituent compositions and comprising a cylindrical chamber having a piston slidably disposed therein, said cylindrical chambers being of different diameters, correlating means controlling the operation of the first and second feeding means according to an operating ratio equal to the inverse ratio of the diameters of the first and second cylinders, said correlating means being adjustable for varying the effectiveness of said operating ratio to vary the ratio of the quantities of the compositions fed and maintaining constant the total quantity of the compositions fed.
 5. Apparatus as set forth in claim 4 wherein said correlating means comprises a pivoted member connected to the two pistons and further including operating means for moving said correlating member about its pivot and connected to said correlating member between said piston connections to said correlating member, the ratio of the distances between the connections of the first and second pistons and the operating means being equal to the inverse ratio of the diameters of the first and second chambers.
 6. Apparatus according to claim 5 including means to adjust the distance between said pivot and the connection of the operating means for varying the ratio of the respective quantities fed by the first and second feedinG means and maintaining constant the total quantity of the compositions fed.
 7. Apparatus according to claim 5 including means to vary the extent of movement of the correlating member for varying the total quantity of the compositions fed and maintaining constant the ratio of the respective quantities fed by the first and second feeding means. 